As our phones and smart devices keep getting faster and more connected, the airwaves that carry their signals—known as the wireless spectrum—are getting crowded.
With 5G networks expanding and 6G on the horizon, the need for better technology to manage all that wireless traffic is growing fast.
Cristian Cassella, a professor at Northeastern University, is tackling this challenge head-on.
He leads the Microsystem Radio Frequency Laboratory, where he and his team are working on tiny, powerful technologies to help wireless networks keep up with demand.
Their work focuses on metamaterials—special man-made materials designed to do things that natural materials can’t.
Cassella recently won a top award from the IEEE European Frequency and Time Forum for his work in this area. And it’s easy to see why—he’s not just tweaking old designs, he’s reinventing how wireless signals can be filtered and sensed at a microscopic level.
To understand why this matters, think about your phone. Every time you use WiFi, Bluetooth, or mobile data, your phone receives many different signals all at once.
Inside the phone, radio frequency (RF) filters help sort those signals and send them to the right place, much like a telephone operator connecting calls. But these filters are based on designs that are decades old—and they’re starting to show their limits.
Cassella’s solution uses new types of microelectromechanical systems (MEMS) built with piezoelectric materials—materials that produce sound waves when electricity flows through them.
By shaping and controlling these acoustic waves at a very tiny scale, his team can create more precise and powerful filters that can handle more signals without interference.
This could be a major boost for future 6G networks, which will rely on even faster data speeds and more connected devices.
But Cassella’s technology has potential beyond wireless communication. These tiny metamaterial devices can also be used for highly sensitive sensors.
In fact, one of his studies, published in Nature Communications, shows how they could detect something as small as the mass of a single blood cell. That level of detail could open the door to new medical tests or tools that monitor health in real time.
Cassella says this kind of sensing was previously impossible because the devices were too small and couldn’t generate strong enough signals. Now, with his team’s innovations, these devices can finally pick up faint signals with enough clarity to be useful.
Whether it’s making our phones smarter or helping doctors detect diseases earlier, these tiny technologies could have a massive impact on the future.
